Noncontrolling Interests, Partnerships and Joint Ventures (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in redeemable noncontrolling interests
Redeemable noncontrolling interests, beginning balance	$ 529,258	$ 525,271
Purchase of redeemable units	(4,976)	(217)	$ (353)
Fresh start accounting fair market value adjustment for purchased units	(924)	(45)
Change in redemption value of partnership units	(18)	(4,249)
Net income attributable to noncontrolling interests	41,288	40,753
Distributions to noncontrolling interests	(41,288)	(40,753)
Redeemable noncontrolling interests, ending balance	523,376	529,258	525,271
Six Flags over Texas
Changes in redeemable noncontrolling interests
Redeemable noncontrolling interests, beginning balance	246,744	243,756
Purchase of redeemable units	(3,440)	(217)
Fresh start accounting fair market value adjustment for purchased units	(720)	(45)
Change in redemption value of partnership units	(11)	(3,250)
Net income attributable to noncontrolling interests	20,634	20,452
Distributions to noncontrolling interests	(20,634)	(20,452)
Redeemable noncontrolling interests, ending balance	242,595	246,744	243,756
Six Flags over Georgia
Changes in redeemable noncontrolling interests
Redeemable noncontrolling interests, beginning balance	282,514	281,515
Purchase of redeemable units	(1,536)	0
Fresh start accounting fair market value adjustment for purchased units	(204)	0
Change in redemption value of partnership units	(7)	(999)
Net income attributable to noncontrolling interests	20,654	20,301
Distributions to noncontrolling interests	(20,654)	(20,301)
Redeemable noncontrolling interests, ending balance	$ 280,781	$ 282,514	$ 281,515

Fresh Start Adjustment Increase (Decrease), Redeemable Noncontrolling Interest

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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The cash outflow during the period for redemption of redeemable noncontrolling interests.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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